The long-term goal of the proposed study is to demonstrate that Chen Medium (CM), developed in our laboratories, is safe and effective for kidney preservation and superior to the University of Wisconsin (UW) solution. The specific aims are to test the feasibility of utilizing CM for kidney preservation. In organ transplantation, the quality of the donor kidney is a significant determinant of surgical outcome. Grafting of a poorly preserved kidney may result in delayed kidney function and increased risk of graft failure. Studies show that the storage conditions with UW are not optimal, and that CM may be superior to UW for tissue preservation. When tested in the cornea model in animals and humans, CM is effective to help the cornea sustain viability for up to 14 days, and yield a clear graft promptly after surgery with excellent graft success rates. CM has been approved by FDA for preservation of human corneas for transplantation. The proposed study will be carried out using the isolated perfused kidney model in rabbits and the auto- transplantation model in dogs with 3-day kidney storage. Effectiveness of tested media will be evaluated in terms of kidney physiologic functions, including Na+ re-absorption, and creatinine and protein clearances. The proposed study, if successful, will enable us to provide an improved media for kidney preservation, and enhance the ability to treat patients requiring renal transplantation. The potential to reduce health care costs and to conserve scarce donor kidneys for transplantation will be maximized. PROPOSED COMMERCIAL APPLICATIONS: The proposed research, if successful, will have potential commercial application. That is, CM will be able to be marketed as a kidney preservation medium. This is an Orphan product with a market size estimated about $20 million a year in the US and about $6-$10 millions for the foreign market combined.